Draft gear housing



Oct. 30, 19.56 R. B. COTTRELL. 2,768,755

DRAFT GEAR HOUSING Original Filed May 19, 1948 2 Sheets-Sheet l Oct- 30,1956 R. B. COTTRELL DRAFT GEAR HOUSING 2 Sheets-Sheet 2 Original FiledMay 19, 1948 United States Patent DRAFT GEAR HOUSING Robert B. Cottrell,Chicago, Ill., assignor to American teel Foundries, Chicago, Ill., acorporation of New ersey Original application May 19, 1948, Serial No.28,011,

n ow Patent No. 2,670,856, dated March 2, 195ML Digglegnd thisapplication August 25T, 195B, Serial No.

6 Claims. (Cl. 213-32) This invention relates to railway draft gears andmore particularly to a draft gear housing of economical and sturdyconstruction having the characteristic of relatively great capacity andquick release.

This application is divided out of my copending application, Serial No.28,011, filed May 19, 1948, for Draft Gear.

A general object of the invention is to devise a steel draft gearhousing which is capable of expansion and contraction without permanentdeformation during compression and release respectively, of saidmechanism.

A more specific object of the invention is to devise a draft gearhousing, such as above described, wherein the open friction end isgenerally oval in shape and is reinforced by a pair of opposed C-shapedexternal flanges arranged in alignment along the long axis of the openend of the housing, the anges acting as spring means to yieldinglyresist expansion of the housing as the friction mechanism is urged intothe open end thereof under the severe impacts of railway service.

The foregoing and other objects and advantages of the invention willbecome apparent from a consideration of the following specification andthe accompanying drawings, wherein:

Figure 1 is a perspective view of a draft gear embodying the novelhousing with portions of the device broken away to clarify theconstruction;

Figure 2 is a side elevational view partly in section of the gear shownin Figure 1; v

Figure 3 is a side elevational View partly in section taken from thebottom of Figure 2;

Figure 4 is a sectional view taken on the line 4-4 of Figure 3; p Y

Figure 5 is a plan view of the housing taken from the open end thereof;

Figure 6 is a side elevational view of the housing;

Figure 6A is a fragmentary sectional view on the line A-A of Figure 6;

Figure 7 is a plan view of the outer wedge follower; v .Figure 8 is aside elevational view partly in section taken from the bottom of Figure7;

Figure 9 is a side elevational view partly in section taken from theright of Figure 7;

Figure 10 is a sectional view taken on the line 1010 of Figure 9, and

Figure 11 is a sectional view on the line 11-11 of Figure 7.

Describing the invention in detail and referring first to theperspective view of Figure l, the gear comprises a novel housing,generally designated 2, with a friction mechanism, generally designated4, receivable Within the open end 6 of the housing. Movement of thefriction mechanism 4 into the housing is resisted by friction developedthereagainst, as hereinafter described, and by an outer coil spring 8seated against the closed end of the housing and an inner coil spring 12seated on a spring support boss 14 formed on the inner end of thehousing. The parts are held in assembled relationship by a bolt PatentedOct. 30, 1956 and nut assembly 16 which, as best seen in Figures 2 and3, extends through the inner spring 12 through an opening 18 in the boss14 and comprises a head 20 engageable with the boss to limit the releasestroke of the clutch mechanism.

The housing 2 is generally oval in shape, as best seen in Figures 1, 4and 5, and comprises the before mentioned open end 6 having frictionsurfaces 22 arranged along the long axis thereof and friction surfaces24 arranged along the short axis thereof, as best seen in Figures 4 and5. Each of the friction surfaces 24 comprises a fiat area 26 disposedintermediate spaced arcuate areas to prevent relative rotation of theassociated shoes.

The housing 2 is shown in detail in Figures 5, 6 and 6A and, as abovenoted, comprises a generally oval friction end having a short axis A(Figure 5) and a long axis B. The arcuate portions of each frictionsurface 24 which is disposed at one side of the long axis B are struckfrom a common center disposed at the opposite side of the long axisalong a radius, indicated at R. Each friction surface 22, as shown inFigure 5, is disposed at one side of the short axis A and is struck froma center Y at the same side of the axis A along a radius designated R.This novel arrangement of friction surfaces has been found to developadequate friction while maintaining the friction mechanism 4 againstrelative rotation with respect to the housing, as hereinafter discussed.

The housing 2 at its open end is formed with a pair of opposed C-shapedanges 28 arranged along the long axis thereof, each of said flangesbeing reinforced centrally thereof by longitudinal ribs 30 and beingreinforced at its respective ends by longitudinal ribs 32 (Figures l, 2and 6).

The housing 2 is also reinforced at its closed end by a pair of internaliianges or ribs 31, as best seen in Figures 2 and 6A, the ribs 31 beingin alignment with the overlapping ends of the ribs 30.

This construction controls elastic deformation of the housing as thefriction mechanism 4 is urged into the open end 6 thereof duringcompression of the gear, and the C-shaped anges 28 act as springs toyieldingly resist such deformation and to prevent permanent distortionof the housing. In this connection it may be noted that in a gear of theabove described type, as is well known to those skilled in the art, thehousing expands as the friction mechanism is urged into the same underthe severe impacts of railway service and after pressure against thefriction mechanism has been relieved, contraction of the housing acts incombination with the springs 8 and 12 to urge the mechanism outwardly tothe release position illustrated in the drawings. As above mentioned, ithas been found that the spring anges 28 accommodate the necessarycontraction and expansion of the housing and prevent permanentdistortion thereof. The flanges 28 are prefer-ably tapered toward theshort axis of the housing to reduce bending stresses along the surfaces24.

The clutch mechanism 4 comprises a pair of substantially identical outershoes 34, each of which comprises a friction face 36 (Figures 3 and 4)complemental to and engaged with the related housing surface 26, and theshoe 34 also comprises spaced outer wedge faces 38 land an intermediategroove 4l) engaged respectively with complementary wedge faces 42 and anintermediate tongue 44 of an outer Wedge follower 46, shown in detail inFigures 7 to 1l inclusive. The outer wedge follower comprises a centralrecess 48 and an opening 50 accommodating the before mentioned bolt `andnut assembly 16.

The outer shoes 34 are in wedge engagementvwith the equalizer 64 as at60 and are in tongue and groove interlock therewith at 62.

The inner shoes 73 comprise radially outer friction surfaces 80 engagedwith the friction surfaces 22 of the housing, as best seen in Figures 2and 4. Each shoe 78 also comprises a wedge surface 84 on its axiallyinner surface having complementary wedge engagement with a spring cap 86(Figures 2 and 3). The spring cap bears against the spring 8 which actsin parallel with the spring 12 to resist the compression stroke of thegear. The shoes 78 are in wedge engagement at 70 with the equalizer 64`and are in tongue and groove interlock therewith at 72.

Thus it will be seen that the novel draft gear housing is provided withshoe interlocking means and comprises resilient means in the form ofopposed C-shaped flanges disposed around the outer perimeter of thehousing at the friction end thereof for controlling elastic deformationof the housing on the compression stroke of the gear and for contractingthe housing to urge the friction shoes outwardly of the open end thereofon the release stroke of the gear.

I claim:

l. In a draft gear, a hollow steel housing having an open end capable ofexpansion and contraction responsive to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and internal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially spacedC-shape flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long axis and their endsextending toward and terminating in spaced relation to said short axis.

2. In a draft gear, a hollow steel housing having an open end capable ofexpansion and contraction responsive to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and intemal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially spacedC-shape flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long axis and their endsextending toward and terminating in spaced relation to said short axis,the medial portion of each flange merging with and being reinforced byan external rib extending longitudinally of the housing.

3. In a draft gear, hollow steel housing having an open end capable ofexpansion and contraction responsive to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and internal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially spacedC-shaped flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long axis and their endsextending toward and terminating in spaced relation to said short axis,the medial portion of each flange merging with and being reinforced by apair of external ribs extending longitudinally of the housing.

4. In a draft gear, a hollow steel housing having an open end capable ofexpansion and contraction responsive to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and internal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially.spacedC-shape flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long axis and their endsextending toward vand terminating in spaced relation to said short axis,tne medial portion of each flange merging with and being reinforced byan external rib extending longitudinally of the housing, the ends ofsaid flanges merging with and being reinforced by other ribs provided onand extending longitudinally of the housing.

5. In a draft gear, a hollow steel housing having an open end capable ofexpansion and contraction responsive to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and internal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially spacedC-shape flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long axis and their endsextending toward and terminating in spaced relation to said short axis,the medial portion of each flange merging with and being reinforced byan external rib extending longitudinally of the housing, a frictionmechanism including friction shoes slidably engaging related frictionsurfaces during compression of the draft gear, said friction mechanismincluding means operative to urge said shoes radially against relatedfriction surfaces.

6. In a draft gear, a hollow steel housing having an open end capable ofexpansion and contraction responsive'to compression and release of thedraft gear, said open end being generally oval-shape and provided withinternal outwardly flaring friction surfaces at each side of its longaxis, and internal outwardly flaring friction surfaces at each side ofits short axis, and diametrically opposed circumferentially spacedC-shape flanges on the exterior of the open end of the housing withtheir medial portions disposed on said long yaxis and their endsextending toward and terminating in spaced relation to said short axis,the medial portion of each flange merging with and being reinforced byan external rib extending longitudinally of the housing, a frictionmechanism including friction shoes slidably engaging related frictionsurfaces during compression of the draft gear, said friction mechanismincluding wedge means operative to urge said shoes radially againstrelated friction surfaces.

References Cited in the file of this patent UNITED STATES PATENTS

